diff options
Diffstat (limited to 'support')
-rw-r--r-- | support/support.h | 2 | ||||
-rw-r--r-- | support/support_stat_nanoseconds.c | 40 |
2 files changed, 34 insertions, 8 deletions
diff --git a/support/support.h b/support/support.h index b0352726bf..e023d00857 100644 --- a/support/support.h +++ b/support/support.h @@ -142,7 +142,7 @@ static __inline bool support_path_support_time64 (const char *path) } /* Return true if stat supports nanoseconds resolution. */ -extern bool support_stat_nanoseconds (void); +extern bool support_stat_nanoseconds (const char *path); __END_DECLS diff --git a/support/support_stat_nanoseconds.c b/support/support_stat_nanoseconds.c index c0d5b2c3a9..6a9e49cc88 100644 --- a/support/support_stat_nanoseconds.c +++ b/support/support_stat_nanoseconds.c @@ -16,16 +16,42 @@ License along with the GNU C Library; if not, see <https://www.gnu.org/licenses/>. */ +#include <errno.h> +#include <fcntl.h> +#include <support/check.h> +#include <support/support.h> +#include <support/timespec.h> #include <stdbool.h> +#include <sys/stat.h> +#include <sys/types.h> +#include <unistd.h> bool -support_stat_nanoseconds (void) +support_stat_nanoseconds (const char *path) { - /* s390 stat64 compat symbol does not support nanoseconds resolution - and it used on non-LFS [f,l]stat[at] implementations. */ -#if defined __linux__ && !defined __s390x__ && defined __s390__ - return false; -#else - return true; + bool support; +#ifdef __linux__ + /* Obtain the original timestamp to restore at the end. */ + struct stat ost; + TEST_VERIFY_EXIT (stat (path, &ost) == 0); + + const struct timespec tsp[] = { { 0, TIMESPEC_HZ - 1 }, + { 0, TIMESPEC_HZ / 2 } }; + TEST_VERIFY_EXIT (utimensat (AT_FDCWD, path, tsp, 0) == 0); + + struct stat st; + TEST_VERIFY_EXIT (stat (path, &st) == 0); + + support = st.st_atim.tv_nsec == tsp[0].tv_nsec + && st.st_mtim.tv_nsec == tsp[1].tv_nsec; + + /* Reset to original timestamps. */ + const struct timespec otsp[] = + { + { ost.st_atim.tv_sec, ost.st_atim.tv_nsec }, + { ost.st_mtim.tv_sec, ost.st_mtim.tv_nsec }, + }; + TEST_VERIFY_EXIT (utimensat (AT_FDCWD, path, otsp, 0) == 0); #endif + return support; } |